Techno-economic Optimization of the Combined Supercritical Carbon Dioxide and Air Brayton Cycles Driven by Copper-Based Chemical Looping Combustion

The chemical looping combustion (CLC)-driven power generation system has great potential for application. In this study, a direct CLC-driven combined supercritical carbon dioxide and air Brayton cycle with near-zero carbon emissions (CLC-sCO₂-BC) is proposed. After revealing the thermodynamic performance advantages of the proposed system, we comprehensively compared the thermoeconomic performance of CLC-sCO₂-BC with and without preheating and optimized the performance of the two layouts using an immune genetic algorithm. The results show that the proposed system has a net power advantage of 1.15 MW and an efficiency gain of 2.30 percentage points compared to the Allam-Z cycle. The preheating mode can enhance the thermoeconomic performance of the proposed system by increasing the temperature of recycled CO₂ in the fuel reactor. The optimization results confirm that the preheated layout achieves a thermal efficiency improvement of 2.78 percentage points and a levelized cost of electricity reduction of $7.35/MWh over the basic layout. Meanwhile, the preheated layout lowers the optimal gas turbine inlet temperature and increases the optimal CO₂ compressor inlet pressure.